Many working implements, such as lawn trimmers, utilize a small motor coupled to a working head through a rotating drive cable. These rotating drive cables are inadequate to support the weight and torque of the working head. As such, the drive cable is positioned concentrically or coaxially within a larger diameter casing or frame tube. However, if an excessive amount of torque is applied to the drive cable, the cable may buckle or twist within the frame tube. Furthermore, with a high rotational speed, the drive cable may chatter within the frame tube, causing a noise problem and creating excessive friction which may harm the drive cable.
To lessen the problems associated with the mounting of a rotating cable within a housing periodic spacers have been developed. These spacers are typically in the form of an intermediate support member or coaxial drive cable centering apparatus. The support member includes a central tube or sheath in which the cable is positioned and an annular array of fins extending radially out from the central sheath. The fins provide a snug fit between the sheath and the outer frame tube. These fins however do not always provide a smooth transition when the frame tube is curved, as with lawn trimmers and the like, again resulting in the creation of excessive heat and noise.
Accordingly, it is seen that a need exists for a coaxial drive cable centering device or support member which may better position a drive cable within an outer frame tube. It thus is to the provision of such that the present invention is primarily directed.